Webbing is commonly attached to a furniture frame member by hand. The webbing is typically attached to one side of a wooden frame by staples. The user then stretches the webbing across the frame and staples it to the other side of the wooden frame. This step is repeated for the desired number of pieces of webbing to be attached to the wooden frame. This process is slow and time-consuming. Further, the process does not provide consistent tension of the webbings across the frame.
Sometimes metal (e.g., steel) frames are used in seating applications with elastomeric webbing for strength and durability purposes. In certain applications, such as the contract and medical seating industries, a seating structure must be durable enough to pass stringent cycle and drop tests, such as the ANSI/BIFMA X5.1 Office Chair Test or the ANSI/BIFMA X5.4 Lounge and Public Seating Test. For purposes of passing these tests, traditional methods of attaching a strap of webbing to a steel frame have proven to be a weakness in terms of cost and/or durability.
One type of known method of attaching webbing to steel frames is to sew the webbing into a large loop, which would then be stretched over the width or depth of the steel frame. This method requires twice the length of webbing as other methods, which can make it cost-prohibitive.
A more common method has been to attach multiple individual narrow (e.g., between approximately 2 inches and approximately 3 inches) web straps. Such straps are traditionally attached to a steel frame by means of several variations of triangular wire hooks, either clamped or sewn to the web straps, with each hook end inserted into a corresponding hole in the steel frame. Typically, approximately 4 or 5 straps are used per seat. Improved methods of attaching multiple individual web straps to a steel frame are described in U.S. Pat. Nos. 9,078,524 and 9,560,916.
Such methods require the fabrication and installation of multiple individual web straps for a single seat and thus have a relatively low efficiency. In addition, the multiple individual web straps may provide uneven support to an occupant of the seat and thus may cause discomfort. To address this, it is sometimes preferred to unitize the individual web straps, which requires additional fabrication and labor.
Consequently, there is a need for an improved sheet webbing attachment to a metal frame.